Exam 2- Respiratory Flashcards
What would be the best way to stop continuous sneezing in a dog?
Intranasal application of a topical anesthetic
Why do bronchodilators sometimes decrease coughing?
Primary stimulus for coughing due to bronchoconstriction
-Bronchodilators administered to help decrease constriction
What are the limitations for using dextromethorphan or antihistamines as cough suppressants in dogs?
a. Short half-life
b. Limited bioavailability- dextromethorphan
Which opioid has the least antitussive effect?
Oxymorphone
How much evidence supports the use of Hydrocodone as an antitussive?
Gold standard narcotic antitussive, direct suppression of cough reflex in the medullary cough center
How much evidence supports the use of Butorphanol as an antitussive?
Excellent antitussive, alternative to Hydrocodone
How much evidence supports use of Maropitant as an antitussive?
Neurokinin receptor antagonist, no anti-inflammatory effects but will decrease cough
How much evidence supports the use of Diphenoxylate as an antitussive?
Crosses the BBB to target opioid receptors in the medullary cough center; used in chronic bronchitis/tracheal collapse treatment
What benefits does furosemide have in managing pulmonary edema in addition to its diuretic effect (that decreases preload)?
a. Diuretic action
b. Produces local vasodilatory prostaglandin in the lung
What benefit do opioids have in managing dyspnea besides sedation?
Desensitizes CO2 receptors
What drug is best suited to decrease pulmonary hypertension w/o having prominent effects on systemic BP?
Sildenafil
What are the benefits of using a glucocorticoid inhaler versus systemic administration? Name one example of an inhaled steroid.
a. Glucocorticoid inhalers produce less systemic side effects, act locally in the lungs, & have higher first pass effects compared to systemic administration of glucocorticoids
b. Examples:
i. Fluticasone
ii. Beclomethasone
iii. Ciclesonide
Feline asthma & equine COPD are primarily problems involving inhalation or exhalation?
Exhalation problems
What is a heave line in a horse & why does it occur?
Heave line- abdominal muscles in horse w/ heaves will enlarge due to chronic overuse
What are the most common side-effects of beta2 agonist bronchodilators?
Tachycardia
Lowering serum potassium
Airway inflammation
Explain how to perform an atropine-challenge test in equine COPD.
Give dose IV
Diminished heave line→ horse may be responding positively to bronchodilators
Does not provide definitive diagnosis
Major beta2 agonist bronchodilators used in horses- ROA & side-effects
Albuterol- inhaled, airway inflammation
Clenbuterol- oral, alters muscle function
Major beta2 agonist bronchodilators used in humans- ROA & side-effects
Levalbuterol- inhaled, tremors, headaches, dizziness
Terbutaline- parenteral, tremors, dizziness
Why are glucocorticoids often given to animals receiving chronic beta-2 bronchodilators?
Sensitizes beta receptors to the actions of agonists
What major benefit does Theophylline provide in respiratory disease beyond bronchodilation?
Increases the strength of resp. muscles, especially the diaphragm
What are three methylxanthine compounds?
Caffeine
Theobromine
Theophylline
How does Aminophylline differ from Theophylline?
Aminophylline- water-soluble salt of Theophylline; IV or oral
Theophylline- oral only
What effect does oxygen have on the pulmonary vasculature?
Vasodilation
What toxicity signs are most seen with a Theophylline overdose?
Seizures, cardiac arrhythmias, vomiting
What are the best methods for promoting expectoration?
Guaifenesin, saline expectorants, volatile oils
Name the drugs used as expectorants, their proposed MOA, & their effectiveness
a. Expectorants- stimulation of the tubulo-acinar glands
i. Avoid use of cholinergic drugs, creates undesirable side-effects
b. Guaifenesin
i. Dog at 50mg/kg po= no effect
ii. Rat 250mg/kg po= 2x increase
iii. Cat 1000mg/kg po required for consistent change
c. Saline expectorants
i. Ammonium chloride
ii. Potassium or calcium chloride
iii. Sodium or potassium citrate
iv. Ammonium carbonate
d. Volatile oils
i. Eucalyptus
ii. Menthol
Explain the benefit to an animal with respiratory foam due to pulmonary edema of bubbling oxygen through a 20% ethanol solution.
a. Ethanol acts as a surfactant that breaks up the bubbles/dries out the foam
What is the only analeptic drug used in veterinary medicine and what toxicity is associated with its overdose?
a. Doxapram
i. Increases respiration during apnea or depressed respiration
ii. Very small therapeutic index→ give repeat doses cautiously if at all
iii. CNS overstimulation – seizures
What are the primary respiratory side effects associated with Antihistamine use in any species?
Drying out of the resp. tract
What are the primary resp. side effects associated with Bromide use in cats?
Pneumonitis
What are the primary resp. side effects associated with Cisplatin use in cats?
Pulmonary edema
Volume overload, especially in cardiac failure or renal failure patients
What are the primary resp. side effects associated with Nebulized Acetylcysteine in any species?
Bronchospasm, type I hypersensitivity
